I'm in the plan stanges of putting in a kennel. I interested in hearing what substances shoudl be used for the absorption ( example: sand, pea gravel, cedar shaving?) Any help would be much appreciated

This is what I used in my kennel runs for the last 20 years. I've been happy with it. I couldn't use concrete without putting in gutters and drains.

Dig down about 2+ inches deeper than 1 or better 2 gray-blocks put on their side. Line the hole with whatever you want to cut down on "sinkage" of the gravel, I used old newspaper about 1.5 inches thick.

Sink your kennel side wire barriers now if wanted.

A friend with way more money than me put a layer of river-rock in here. I skipped that and didn't see any difference in gravel loss or sanitation. Her ground was boggier than mine. My kennels were a mix of sand and clay.

Line the run with the gray-block put HOLE SIDE UP. This is for drainage, plus discourages digging, and also contains the gravel from sinking.

Layer over with gravel, and put a layer well over the top of the blocks so it's deepest in the middle of the kennel.

I scooped my runs a couple times a day. In winter, the poop doesn't stick to this surface, although I did pick up some gravel with it. I would hose with Duall (industrial / morgue sanitizer and deoderant) as needed. I didn't have much parasite problem, and the drainage was great.

Because the soil was so much clay, water would run off a plain concrete surface and pool. This encouraged the water down.

Maytags used this in their kennel and exercize yards too, and had good luck. Kind to feet, and if you have a poop eater, the pea gravel won't impact them. I wouldn't ever use anything bigger than pea gravel where the dogs could reach it.

Only drawback, the gravel will sink and needs added to about every couple years.

My kennel is actually on the far sid of my patio. It initially had dirt flooring but mud became a real issue in the winter and early spring.

The kennel is now on a cement floor. The bottom of the kennel is raised slightly (maybe 2 inches), enough that I can scrape out the waste. The waste is scraped right onto a dirt surface where I am able to shovel it up and dispose of it. The urine drys on the cement but can be scrubbed and sprayed and the cement comes clean. I find that this is much more sanitary than the dirt flooring and seems to be fairly low maintenance. I scrape daily and scrub weekly, with a few spray downs in between.